Various treating implements exist which include movable treating elements on the head portion of the implement. For example, power toothbrushes frequently have a brush head connected to the handle wherein at least a portion of the brush head rotates continuously in one direction or oscillates back and forth. Other treating implements which may have movable treating elements include, for example, electric razors, clippers, massage devices and various other personal grooming devices.
An example of a power operated toothbrush having an oscillating disk on its cleaning head is found in WO 03/02453. Such toothbrush includes a drive rocker coupled with a motor by a cam. The end of the drive rocker is fixedly mounted to the cam in a position eccentric to the motor shaft. As a result, when the motor shaft rotates the cam the drive rocker is moved in a funnel or cone-like manner. The drive rocker is mounted between the motor and the bristle support extending through a ring-shaped bearing element. By mounting the drive rocker between the motor and the bristle support with the bearing element, the drive rocker is fixed to a point so that the drive displacement of the drive rocker describes a double cone, wherein the peaks of the two converging cones lie in the area of the bearing element. The drive displacement of the drive rocker is transformed into the drive displacement of the bristle support.
It would be desirable to provide a drive system which imparts motions to a treating implement such as a power toothbrush wherein the motion is controlled in an effective, yet economical manner. It would also be desirable to provide such a drive system which could effectively operate using a small motor thereby having the treating implement be inexpensive and of small size without detracking from its efficiency.